How Long Marijuana Lasts in Your System

How Long Marijuana Lasts in Your System

How long marijuana remains in your system depends on the potency level of the THC in the marijuana you consume and how often you consume it. Higher THC means it lasts longer.
Jared Rosenthal
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Ingraphic: How Long Marijuana Lasts in Your System

The Answer: How long marijuana stays in your system is highly variable and depends on many factors, including the THC potency (the amount of THC) in the weed and how often you consume it.

The Explanation: Most people don’t realize that if they use weed with a higher THC level, it will stay in their body for longer length of time than marijuana with a lower THC level.

Think about it using this analogy to alcohol: if you consume stronger drinks, you stay drunk for longer. One strong beer at 10% ABV (Alcohol By Volume) is equivalent to 3 light beers at 3.3% ABV. The rationale is similar when it comes to cannabis use. If you’re smoking high THC weed, say 15%, then it will stay in your system a lot longer than 5% THC weed. The frequency of use also matters; more consistent marijuana smokers will retain THC metabolites in their urine for a month or longer, whereas casual smokers will be able to rid their system of the drug much faster.

I recently tested a guy who has just been released from prison. He had 60 days to stay drug-free, otherwise, he’d go back to jail. So, he came to me for drug testing.  He hadn’t used in prison, or in the one week since he got out, yet he tested positive for marijuana and subsequently failed the drug test. Shocked, I asked him to tell me the honest truth. He told me that he was using butane hash oil at 60 to 80% THC prior to getting locked up, but he hadn’t touched it since.

I can safely assume he was being truthful – in the many, many years of testing addicts and non-addicts alike, I’m quite confident in my ability to pick up on someone lying about their drug use. So, if he was, in fact, telling the truth, that means the THC stayed in his urine for well beyond the detection window of drug screenings.  It was a learning lesson for us both on the long-lasting effects high potency THC.

Detecting THC in a urine test beyond two months of non-use is unprecedented. Even hard street drugs like cocaine are gone from the urine in about 5 days – 7 at the most – regardless of the frequency of use. However, the trend of increasing THC in products consumed by marijuana users such as sincemilla (highly potent marijuana also commonly spelled sinsemilla) and BHO (butane hash oil) is obliterating the old-school logic of the amount of time one needs to remain clean to pass a drug test.

We’re often asked, “Does weed show up in a urine drug test?” Well, it’s not as easy to answer that question as it used to be. In short – don’t believe the myths. It has nothing to do with body weight, body fat, or flushing out your system.

The answer is that there is no definite answer. How long marijuana stays in your system comes down to potency and frequency of use.

You can test yourself to check if marijuana comes up in your urine (or hair) with either of these related services:

Health Street offers these and other drug tests at 2500+ DNA Test Locations Nationwide. Find a location for drug testing:

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This article was prepared with my own experience running Health Street, a drug testing company that performs thousands of tests per year. I also researched articles such as these sources:

  • Hallett, Alison (2013-03-28). “How Hash Oil Is Blowing Up Across the U.S. — Literally | Underwire”. Retrieved 2014-02-28.
  • “Why Does Cannabis Potency Matter?”. United Nations Office on Drugs and Crime. 2009-06-29.

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